Empty Spots ($450K each): $ 450,000- You have less than 53 men on your roster. That is fine, but teams cannot keep a smaller roster for cost-savings benefits as that is unrealistic (we cannot have a team only field half a roster, for example, but have 20 highly paid superstars since they can afford it with no other expenses). You do not need to physically have 53 players, but will be charged the minimum rookie contract of $450K for each open spot against the cap so all teams have at least 53 players contributing to their cap.

To ensure that you have some flexibility during the season (when it is more difficult to create cap space), it is advised to stay around $2 million under the cap, so you will have space to make regular season transactions for injuries, etc.